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#include <bits/stdc++.h>
using namespace std;

const int MOD = 1e9 + 7;

int query(const vector<int>& tree, int l, int r) {
  assert(l <= r);
  l += tree.size() / 2;
  r += tree.size() / 2;
  int result = tree[l];
  if (l != r)
    result = (result + tree[r]) % MOD;
  while (l / 2 != r / 2) {
    if (l % 2 == 0) result = (result + tree[l + 1]) % MOD;
    if (r % 2 == 1) result = (result + tree[r - 1]) % MOD;
    l /= 2;
    r /= 2;
  }
  return result;
}

int main() {
  ios_base::sync_with_stdio(false);
  int n;
  cin >> n;
  vector<int> a(n);
  for (int i=0; i<n; ++i)
    cin >> a[i];

  vector<int> p(n + 1);
  p[0] = 0;
  for (int i = 0; i < n; ++i)
    p[i + 1] = (p[i] + a[i]) % MOD;

  vector<int> v = p;
  sort(v.begin(), v.end());
  v.erase(unique(v.begin(), v.end()), v.end());

  int T = 1;
  while (T < (v.size() + 1))
    T *= 2;

  vector<int> tree[2];
  tree[0].resize(2 * T);
  tree[1].resize(2 * T);

  vector<int> dp(n + 1);

  for (int i = 0; i <= n; ++i) {
    int ind = lower_bound(v.begin(), v.end(), p[i]) - v.begin();
    if (i == 0) {
      dp[i] = 1;
    } else {
      dp[i] = (
        query(tree[p[i] % 2], 0, ind) +
        query(tree[(p[i] + 1) % 2], ind + 1, v.size())
        ) % MOD;
    }
    int it = T + ind;
    while (it > 0) {
      tree[p[i] % 2][it] = (tree[p[i] % 2][it] + dp[i]) % MOD;
      it /= 2;
    }
  }

  cout << dp[n] << endl;
}